body{
	overflow: auto;
}
.header-nav{
	position:absolute;
}
.banner{
	background: url(../images/zuzhi.jpg) no-repeat center;
	background-size:cover;
-webkit-background-size: cover;
-o-background-size: cover;
-ms-background-size: cover;
-moz-background-size: cover;
position:relative;
/*min-height: 950px;*/
transition: 1s;
-ms-transition: 1s;
-webkit-transition: 1s
}
.tissue img{
	margin: 52px auto 209px;
}
